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71.
Pomerantz AE Ausfelder F Zare RN Juanes-Marcos JC Althorpe SC Sáez Rábanos V Aoiz FJ Bañares L Castillo JF 《The Journal of chemical physics》2004,121(14):6587-6590
Experimental measurements of rovibrational product state distributions for the inelastic scattering process H + D2(nu=0,j)-->H + D2(nu' = 1,2,j') are presented and compared with the results of quasiclassical and quantum mechanical calculations. Agreement between theory and experiment is almost quantitative. Two subtle trends are found: the relative amount of energy in product rotational excitation decreases slightly with increasing collision energy and increases slightly with increasing product vibrational excitation. These trends are the reverse of what has been found for reactive scattering in which the opposite trends are much more pronounced. 相似文献
72.
Brouard M Burak I Marinakis S Minayev D O'Keeffe P Vallance C Aoiz FJ Bañares L Castillo JF Zhang DH Xie D Yang M Lee SY Collins MA 《Physical review letters》2003,90(9):093201
The absolute value of the cross section for the abstraction reaction between fast H atoms and H2O has been determined experimentally at a mean collision energy of 2.46 eV. The OH population distribution at the same mean energy has also been determined. The new measurements are compared with state-of-the-art quantum mechanical and quasiclassical scattering calculations on the most recently developed potential energy surface. 相似文献
73.
Cao Thi Vi Ba Ha Huy Bang Dang Van Soa 《International Journal of Theoretical Physics》2003,42(8):1781-1786
We propose commutation relations for a single mode -deformed para-Bose oscillator. In this new deformation of para-Bose statistics the distribution function has the same form as in the para-Bose statistics. Furthermore, we show analogies between the coherent states of -deformed and q-deformed para-Bose statistics. 相似文献
74.
Experimental arrangement consisting of spontaneous parametric down converter with type-I phase matching (SPDCI) and a beam splitter with unitary Hadamard transformation is proposed for conditional preparation of macroscopic entangled states. The given method requires no photon number resolving detection to generate most probable macroscopic entangled state. We calculate the amount of entanglement stored in the macroscopic entangled states and develop a method to increase the amount of entanglement stored in the state. 相似文献
75.
This work describes a novel type of working electrode for use in voltammetry and polarography — the renewable silver liquid amalgam film–modified silver solid amalgam annular band electrode (AgLAF–AgSAE). The electrode is produced by mechanically refreshing the silver liquid amalgam film (AgLAF) before each measurement. The main constituents of the electrode are: a specially constructed silver solid amalgam annular band electrode (AgSAE), two silicon O-rings, silver liquid amalgam and a polypropylene electrode body. Contaminants from the analyzed solution are removed and the AgSAE surface is covered with a thick layer of fresh amalgam while pulling the AgSAE into the sensor body. During movement in the reverse direction AgLAF is formed and homogenized. The time needed to refresh the film is less than 1 s. The electrode is characterized by excellent surface repeatability (~ 1%) and long-term stability (over ten thousand measurement cycles). 相似文献
76.
We develop a method for adaptive mesh refinement for steady state problems that arise in the numerical solution of Cahn–Hilliard equations with an obstacle free energy. The problem is discretized in time by the backward-Euler method and in space by linear finite elements. The adaptive mesh refinement is performed using residual based a posteriori estimates; the time step is adapted using a heuristic criterion. We describe the space–time adaptive algorithm and present numerical experiments in two and three space dimensions that demonstrate the usefulness of our approach. 相似文献
77.
A theoretical approach to polycondensation reaction of Aa-Bb type Involving intramolecular cycllzatlon has been proposed by Tang Au-chin et al.. In this paper, the theoretical sol-gel distribution is tested by polycondensation of adipic acid with trimethylol propane in a sto-ichiometric ratio of 0. 8, and the effect of intramolecular cyclization is discussed in detail. 相似文献
78.
In this study, electron paramagnetic resonance of γ-irradiated single crystals of N-Trifluoroacetyl-α-amino isobutyric acid (F3Ac-Aib-OH) was investigated at room temperature and analyzed for different orientations of the crystal in the magnetic field. The paramagnetic species in N-Trifluoroacetyl-α-aminoisobutyric acid was attributed to the ?F2-R radical (R= CONHC(CH3)COOH). Hyperfine coupling constants and g value were also determined. In addition, the single crystal of F3Ac-Aib-OH was UV-irradiated and paramagnetic species formed was studied at room temperature. The effects of gamma irradiation on fluoroamino acid and stability were discussed. 相似文献
79.
80.